How can I speed up my Google Spreadsheet Script?

I am somewhat new to JavaScript and very new to using it in Google Spreadsheets. I have read that fewer calls to Google Spreadsheet API speeds things up, but I feel like I have as few as possible at this point.

I have a spreadsheet for a D&D like role playing game and I have it set up so certain tabs are hidden/shown depending on the class(es) selected. The spreadsheet also hides/shows certain columns/rows depending on if the character has 2 weapons or one and the number of attacks the character has, which is based on class and level.

var attackMathRange = AttackMath.getRange("A1:C48").getValues()
// note that arrays are zero based
// so C maps to 2 and 8 maps to 7
var twoWeapons = attackMathRange[2][7]
// slice to get a range of values
// slice gets all values from first index up to
// but NOT including the second index
var twoWeaponTable = attackMathRange[0].slice(29, 48)

Every call you can reduce will speed up the script. You could even just get the entire range of values on a sheet, make adjustments appropriately, then use range.setValues once all changes are complete.